hadoop.spec && systemd && cgroups.

[Tim St Clair]

Rob - 

We will "eventually" need to provide integration points inside of the systemd scripts, and hadoops cgroup config, so out of the gate it plays nicely.  

Systemd config for cgroups:
http://0pointer.de/blog/projects/resources.html

^^ There is a full list of knobs here: 
http://0pointer.de/public/systemd-man/systemd.directives.html

However, it may require translation as it appears they have recreated names for existing cgroup params:
https://access.redhat.com/site/documentation/en-US/Red_Hat_Enterprise_Linux/6/html/Resource_Management_Guide/

We will then need to match up the config settings ref'd

here: 
https://issues.apache.org/jira/browse/YARN-160

& here (search for cgroup):
http://hadoop.apache.org/docs/r2.0.4-alpha/hadoop-yarn/hadoop-yarn-common/yarn-default.xml

Cheers,
Tim